The utility model provides a snap judgments coaxial cable BNC radio frequency head fault type's indicator utilizes to form the connection in series -parallel relation between the pilot lamp and the volume of awaiting measuring coaxial cable's the heart yearn, shielded wire, causes the bright change of going out of pilot lamp to judge when forming the short circuit or opening circuit to power when shielding a shortcoming or fault the way with two resistor strings income circuit china insurance company, ltds. Among the one end access circuit with the direct butt joint of two BNC, connect the BNC radio frequency head when other end is used for testing respectively, instruct heart yearn and shielding layer short circuit, the heart yearn of a coaxial cable both ends BNC radio frequency head respectively and trouble such as the heart yearn opens circuit, shielding layer and shielding layer open circuit with three pilot lamp. The utility model relates to a snap judgments coaxial cable BNC radio frequency head fault type's indicator, easy operation, quick, the rate of accuracy is high, compared with traditional universal meter, shortens test time greatly.